Crystal structure and reverse saturable absorption study of two new Schiff base, (E)-N-benzylidene-2-methylaniline and N,N′-methanediylidenedianiline

Two new Schiff base, (E)-N-benzylidene-2-methylaniline (CH3C6H4Ndouble bond; length as m-dashCHC6H5) (1) and N,N′-methanediylidenedianiline (C6H5Ndouble bond; length as m-dashCdouble bond; length as m-dashNC6H5) (2) have been synthesized and characterized by IR and Single crystal X-Ray Diffraction. Their thermal stability was determined by TGA-DSC. Reverse saturable absorption (RSA) nonlinear optical effect has been observed in their methanol solution using open-aperture Z-scan technique with 20 picosecond (ps) pulses at wavelength 1064 nm. Their molecular two-photon absorption cross-section σ2 was determined and the theoretical mechanism was analyzed by simplied five-energy-band model.